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A340718
a(n) is the least k such that A340717(k) = n.
2
0, 1, 3, 5, 7, 9, 11, 15, 17, 19, 21, 23, 27, 31, 33, 35, 37, 39, 43, 45, 47, 51, 55, 63, 65, 67, 69, 71, 73, 75, 77, 79, 83, 85, 87, 91, 93, 95, 99, 103, 107, 111, 119, 127, 129, 131, 133, 135, 137, 139, 141, 143, 147, 149, 151, 153, 155, 157, 159, 163, 165
OFFSET
0,3
COMMENTS
These are also the numbers k such that k <= A030101(k).
All terms, except a(0) = 0, are odd.
For any k > 0, there are A005418(k) terms with k+1 binary digits.
A000225 and A006995 are subsequences.
LINKS
EXAMPLE
k | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, ...
A340717(k) | 0, 1, 1, 2, 1, 3, 2, 4, 1, 5, 3, 6, 2, 6, 4, 7, ...
n | 0, 1, 2, 3, 4, 5, 6, 7, ...
a(n) | 0, 1, 3, 5, 7, 9, 11, 15, ...
PROG
(PARI) is(n) = n <= fromdigits(Vecrev(binary(n)), 2)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Jan 17 2021
STATUS
approved